1. Technical Field
The present disclosure relates generally to communications equipment, and more particularly, to a method and apparatus for optimizing access to Universal Integrated Circuit Card (UICC) files in a User Equipment (UE).
2. Description of Related Art
Restricting the use of a cellular or wireless terminal to a particular purpose or application is a useful feature that has yet to be optimized. Typically, a wireless terminal registers itself on a wireless network when the power is turned on. A smart card, such as a Subscriber Identity Module (SIM) card, which is inserted inside the wireless terminal, contains registration files that allow the wireless terminal to register with a network. For wireless networks such as Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), or Long Term Evolution (LTE), the SIM is just one component of several other modules within a Universal Integrated Circuit Card (UICC).
The UICC is inserted into the wireless terminal, and when the wireless terminal is powered on, registration information, such as an International Mobile Subscriber Identity (IMSI), LOCation Information (LOCI), subscriber information, security keys information, Public Land Mobile Network (PLMN) information, etc., is used to register the wireless terminal with the wireless network. Thereafter, the wireless terminal may use services offered by the wireless network.
Generally, there are several Elementary Files (EFs) (e.g., Transparent type, Linear type, Fixed type, and Cyclic type) defined in a Universal Subscriber Identity Module (USIM) or an Internet Protocol (IP) Multimedia Services Identity Module (ISIM) or a Code Division Multiple Access (CDMA) SIM (CSIM) or any other Network Access Application (NAA) in the UICC specification, where the file size or total number of records and the size of each record is not fixed, and there is a Short File IDentifier (ID) (SFI) value defined in 3rd Generation Partnership Project (3GPP)/European Telecommunications Standards Institute (ETSI) specifications. The ETSI and 3GPP specifications have defined default SFI values for several EFs present in the UICC and the NAA application of the UICC. The SFI values can be used by a UE to perform an “implicit SELECT” operation while performing READ or UPDATE or SEARCH operation on the EFs. Also, there are several EFs whose file size or total number of records and record size are not fixed, as per the specification, and depend on the contents available.
For example, when there is a need to read the complete contents of the EF with the SFI whose file size is not fixed, the SFI value cannot be used for an “implicit SELECT” operation as the total size of the EF is unknown. Hence, an “explicit SELECT” operation is performed on the EF in order to retrieve File Control Parameter (FCP) values of the EF so that the total file size can be determined by the UE. Thereafter, the file size information is used by the UE to send a READ command to the UICC.
Due to the above-described limitations of not having file size information of the EF, the SFI value, even though defined, cannot be used efficiently due to the SELECT operation having to be performed on the EF to query the FCP values. Currently, there is no method of knowing the file size or the total number of records and the size of each record of the EFs, without performing the SELECT operation.
Thus, a need exists for providing a method to optimize access to the UICC files in the UE, thereby decreasing the UICC initialization time and improving the user experience significantly.